Read the number of TLs for VP9 too + cleanup

webrtc/modules/video_coding/main/source/video_sender.cc

Index: webrtc/modules/video_coding/main/source/video_sender.cc
diff --git a/webrtc/modules/video_coding/main/source/video_sender.cc b/webrtc/modules/video_coding/main/source/video_sender.cc
index c5317ec412bb61f4455ec656a2435e85160df1aa..1abf20b48d3ded44a056e0cebec2e3cf73e8a737 100644
--- a/webrtc/modules/video_coding/main/source/video_sender.cc
+++ b/webrtc/modules/video_coding/main/source/video_sender.cc
@@ -19,6 +19,7 @@
 #include "webrtc/modules/video_coding/main/source/video_coding_impl.h"
 #include "webrtc/modules/video_coding/utility/include/quality_scaler.h"
 #include "webrtc/system_wrappers/interface/clock.h"
+#include "webrtc/system_wrappers/interface/field_trial.h"
 #include "webrtc/system_wrappers/interface/logging.h"
 
 namespace webrtc {
@@ -106,12 +107,20 @@ int32_t VideoSender::RegisterSendCodec(const VideoCodec* sendCodec,
     return VCM_CODEC_ERROR;
   }
 
-  int numLayers = (sendCodec->codecType != kVideoCodecVP8)
-                      ? 1
-                      : sendCodec->codecSpecific.VP8.numberOfTemporalLayers;
+  int numLayers;
+  if (sendCodec->codecType == kVideoCodecVP8) {
+    numLayers = sendCodec->codecSpecific.VP8.numberOfTemporalLayers;
+  } else if (sendCodec->codecType == kVideoCodecVP9) {
+    numLayers = sendCodec->codecSpecific.VP9.numberOfTemporalLayers;
+  } else {
+    numLayers = 1;
+  }
+
   // If we have screensharing and we have layers, we disable frame dropper.
   bool disable_frame_dropper =
-      numLayers > 1 && sendCodec->mode == kScreensharing;
+      (numLayers > 1 && sendCodec->mode == kScreensharing) ||
+      (field_trial::FindFullName("WebRTC-DisableGenericBitrateFrameDropper")

[pbos-webrtc, 2015/10/07 11:27:55]

Can we call this WebRTC-Test- or so? I'd like to distinguish between things that
we test with and things that we intend to launch. WDYT?

[ivica, 2015/10/07 11:32:52]

Now when it's so simple, I'm not sure if it's necessary to commit it. Still, for
the same reason it's not a big deal.
I was asked to generate stats and graphs with the frame dropper disabled, and
the good thing of keeping it here is that the script I used to generate all the
graphs will work without modifying the code (script is not in the repository).
I don't know what's best.

+          == "Enabled");
   if (disable_frame_dropper) {
     _mediaOpt.EnableFrameDropper(false);
   } else if (frame_dropper_enabled_) {